No one actually knows how to lculate what speaker cable they need

Oh lovely! Another snake oil guru!

I’m no engineer, but even my sophomoric understanding tells me you’re explanation up there is clearly lacking in technical consideration and reflects a simplistic grasp on the variables at work.

Vtl 250 mono blocks,  speaker is Gradient 1.3  they are 4 feet away from amp,  thank you

All this is eye-of-newt-and-toe-of-frog. Get good, rationally-engineered, not-too-expensive cables (I use Blue Jeans), and keep them matched in length and reasonably short.

Mr. fedie
Your  Vtl 250 mono blocks have a DF of 9.3! (8 ohms / 0.86).
https://www.stereophile.com/content/vtl-225w-deluxe-monoblock-power-amplifier-measurements
At 4' you may use almost any wire. it won't make any difference.

Mr. kosst_amojan

There is nothing in your observation to disapprove nor approve anything. 

I'll use Confucius say:

The one who asks a question, may look fool for a few minutes. The one who don't, will remain fool for the rest of his lives.